Steam-brake



(No Model.)

R. HARDIE.

.STEAM BRAKE.

NQ. 375,933.. Patented Jan. 3, 1888.

UNITED STATES PATENT OFFICE.

ROBERT HARDIE, OF ROME, NEW YORK.

STEAM-BRAKE.

.'PECIFICATION forming part of Letters Patent No. 375,933, dated January 3, 1888.

Application filed March 24, 1887.

.To @ZZ whom, it may concern:

Be it known that I, ROBERTV HARDTE, of Rome, in the county of Oneida and State of New York, have invented a new and useful Improvement in Steam-Brakes for Locomotives and other Railway-Vehicles, of which the following is a specification.

Where brakes are applied to the wheels of locomotives by asuitable piston actuated by steam -pressure within a cylinder, the sudden discharge of exhaust-steam from the brakccylinder is objectionable, in some cases to such an extent as to necessitate the running of the exhaustpipe into the smokebox to carry off the exhaust, and a spring is usually employed for releasing the brake or for making the return movement of the actuatingpiston in a direction the reverse to that in which it is moved by iiuidpressure to put on the brake.

The object of my invention is to construct an apparatus so that the motive iiuid after having performed its work in applying the brake will be employed in releasing the brake,

' thereby being employed in addition to the releasing-spring, or it may be in lieu of such a spring; also to prevent the sudden escape of the exhaust with a roar.

In carrying out my invention I employ, in combination with a brake and brake-applying connections of a railway-vehicle, a cylinder and a piston attached to said connections for operating them, the cylinder affording greater steam-space on one side of the piston than on the other, and having a constantlyopen exhaust from the larger steamspace,and valve apparatus for controlling the admission ot` motive fluid to the smaller steam-space on one side of the piston, and for controlling the exhaust of such motive fluid to the larger steam-space on the opposite side of the piston. The piston may have a hollow trunk,whereby the difference in the duid-space on opposite sides thereof is obtained,and the exhaust from the larger space may be through the hollow trunk.'

The invention consists in novel combinations of parts, hereinabove referred to, and hereinafter described, and pointed out in the claims In the accompanying drawings, Figure l represents such portion of a locomotive and Serial No. 232,223. (No model.)

my improved device secured thereto as is necessary to illustrate my invention. Fig. 2 is a sectional elevation,upon a larger scale,of the brakeapplying cylinder.A Figs. 3 and 4 are sectional views illustrating, upon the same scale as Fig. 2, one form of valve apparatus and connections which may be employed, showing the valve in two different positions; and Fig. 5 is an elevation of such valve apparatus.

Similar letters of reference designate corresponding parts in all the figures.

A A designate the adhesion or supporting wheels of a locomotive, and B B brake-shoes, which are hung by arms B from rock-shafts B2, and are thereby so supported as to permit oftheir swinging toward and from the wheels A. The several brake-shoes B (two being here represented) are actuated by a rod, O, and to this rod is connected a bell-crank lever, O', which is fulcrumed at c to a suitable 'portion ofthe locomotive-frame.

D designates a cylinder, and D' a piston working therein, and serving, when actuated by steam or other motive fluid, to apply the brake. As here represented, the steam or Huid spaces D2 D3, below and above the piston D', are of different sizes or capacities, and if steam, after being admitted to the steam-space Dl to force the piston D upward, be eXhaustedinto the larger steam space, D3, above the piston, a considerable diminution of pressure will occur. The piston D', I have shown as having a hollow piston-rod, D4, provided at thelower end with an outlet, d, governed by a valve or cock, d', and through which steam and the water of condensation may escape. In the hollow piston D is an aperture, d2, through which the space D3 above the piston communicates with the hollow piston-rod D4. The hollow rod D* works through a suit-able stuffing-boX, d3, at the lower end of the cylinder D, and the piston is provided with suit-able packing, d".

EEdesignatepipes,whichlead, respectively, from the lower and upper ends of the cylinder D above and below the piston.

In order to properly operate the apparatus, it is necessary that there be provided a valve apparatus whereby steam may be admitted to the space D2 below the piston, and whereby IOO I0 ff communicate with the pipes E E.

the spaces D2 D3 may be placed in communication with each other. ln the present example of my invention I have shown a. simple plug-valve, F, in a suitable plug-seat, FV, and provided with suitable pipe-connections, ff fzfs. The pipe-connection f, which constitutes the supply for steam or other motive fluid, leads from the boiler or other suitable reservoir, while the connect-ions or branches I have represented the plug F as having formed in one side a port or passage, f4, by which the connection j" and the pipe E', leading to the upper end of the cylinder D, may be alternately placed in communication with the pipeconnectionfand pipe E, leading to the lower end ot' the cylinder D, or with the pipe connection f2, leading to the atmosphere. The interior ofthe plug F is hollow, and has ports ffs, which communicate with corresponding ports in the plug-seat, forming continuations of the pipe-connections ffs. The valve or plugFmay be operated by a suitablehandle, fl.

In the first operation of the apparatus, and in order to apply the brakes B, the valve F is turned to the position shown in Fig.v 3, thereby placing the upper end of the cylinder D in communication, through the pipe E and pipefz, with the atmosphere, and at the same time placing thelower end ofthe cylinder below the piston D',and, through the pipe E and the supply]F3 and portsff, in communication with the steam supply. The steam thus admitted below the piston D raises said piston, and through the links c', which connect the piston-rod Dl1 with the bell-crank lever C', applies the brakes B. iVhen it is desired to release the brakes, the valve-plug F is turned to the position shown in Fig. 4, and by the port or passagef* the pipes E E', which lead from the lower and upper ends of the cylinder D, are placed in communication, the supply of motive ,fluid from the pipe]03 being at the same time shut off by the valve F. The steam, which has performed its work in the steam-space D2 below the piston, then passes through the pipes E E and valve F Finto the space D3 above the piston. It is thereby reduced in pressure; but its force being exerted upon a larger area than the area of the lower side of the piston, the said piston is forced downward and the brake is released. After the brake has been released the exhauststeam escapes slowly from the upper steam space, D3, through the opening or aperture cl2 into the hollow piston-rod D", and this steam, together with the water of condensation, slowly escapes through the outlet d without any material noise. It will be understood that the portf in the plug F and the corresponding port or opening in the plug-seat are below or in a different plane from the portsff.

Vhat I claim as my invention, and desire to secure by Letters Patent, is-

l. The combination,with a brake and brakeapplying connections ofa railway-vehicle, ofa cylinder and a piston'attached to said connecA tions for operating them, the cylinder affording a greater steam-space on one side ol' the piston than on the other, and having a constantly-open exhaust from the larger space, and a valve apparatus i'or controlling the admission of motive duid to the smaller space on one side of the piston, and for controlling` the exhaust of such motive i'luid to the larger space on the opposite side of the piston, substantially as herein described.

2. The combination, with a brake and brakeapplying connections, of the cylinder D and the hollow trunk-piston D', affordingthe steamspaces D2 D, of dilferent size, and the pistou being attached to said brakeapplying connections, and the piston also having an opening, d2, from the space D3 to the hollow trunk and the opening d from ille trunk, and a valve apparatus for controlling the admission of motive Huid to the space Dl and its exhaust from the space D2 to the space D, substantially as herein described.

RO B'l. HARDIE.

Witnesses:

R. H. DOXTATER, GEo. P. NocK. 

